An OpenVPN server comes with pfSense (a free BSD-Unix based firewall that runs on intel boxes). There’s also one on Synology Diskstations (not free, but reasonably priced NASs).

I use OpenVPN regularly when I’m away from home. Mostly just to have access to my media server. It’s easily done but I don’t bother to split access from my mobile devices as there’s some potential benefit from being snooped on when I’m on a wifi net somewhere.